Controlling mute function on telephone

ABSTRACT

A telephone device and a method and for controlling a mute function in the telephone device. While the mute function is active, voice recognition software in the telephone device processes sound detected by a microphone in the telephone device to recognize and identify one or more specific words as having been spoken by a specific person and not by another person, and in response, the telephone device activates an alarm in the telephone device to communicate that the mute function is active. The voice recognition software was trained, prior to the sound having been detected, to differentiate the one or more specific words spoken by the specific person from the same one or more specific words spoken by other people.

This application is a continuation application claiming priority to Ser.No. 11/189,294, filed Jul. 26, 2005, now U.S. Pat. No. 8,787,866 issuedJul. 22, 2014.

FIELD OF INVENTION

The present invention relates generally to telephones, and moreparticularly to control of a mute function on a telephone or other audiocommunication device.

BACKGROUND

It is known for a telephone to include a mute function, typicallyactivated by a user pressing a mute button on the telephone. Once themute function is activated, speech or other sounds reaching thetelephone will not pass through to other people on a call. The mutefunction is typically (but not always) used when the telephone isoperating in a “speaker” mode, where a microphone in the telephone baseunit is activated (instead of a microphone in the handset). The mutefunction is typically used in a conference call at times when the useris not expected to speak, although it could be used as well in a callwith only one other person. Occasionally, while the mute function isactive, the user will attempt to speak to the other person or people onthe call, forgetting that the mute function is active. Because mutefunction is active, the other person or people will not hear the wordsspoken by the user. When the user realizes that the mute function isactive, the user will need to repeat the previously muted words.

U.S. Pat. No. 6,870,919 discloses a telephone with a mute function, anda notification unit which determines when a user is speaking while themute function is active. In such a case, the telephone or a computerprovides a mute status reminder to the user. The mute status remindermay be a tone or prerecorded message. U.S. Pat. No. 6,870,919 alsodiscloses activation of the mute status reminder when the communicationsignal exceeds a predetermined energy level.

An object of the present invention is to avoid unnecessary mute statusreminders.

SUMMARY

The present invention resides in a system, method and program forcontrolling a mute function on a telephone device. While the mutefunction is active, sound reaching a telephone or other communicationdevice is sensed, and a determination is made if the sound includes aword. If so, an alarm is activated to alert a user that the mutefunction is active. If not, the alarm is not activated.

In accordance with an optional feature of the present invention, speechrecognition software is trained to recognize the voice or speech patternof a specific user, and the alarm is activated only if the word wasspoken by the specific user.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a perspective view of a telephone with a hand set, base unitwith a microphone/speaker, mute button and internal function to providea mute status reminder with controls according to the present invention.

FIG. 2 is a block diagram of certain components of the telephone of FIG.1.

FIG. 3 is a flow chart of one embodiment of the mute status reminderfunction of FIG. 1.

FIG. 4 is a flow chart of another embodiment of the mute status reminderfunction of FIG. 1.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention will now be described in detail with reference tothe figures. FIG. 1 illustrates a telephone generally designated 10 inwhich the present invention is incorporated. Telephone 10 comprises aconventional handset 12 with a microphone 14 at one end and a speaker 16at the other end. As shown, the handset 12 resides in its well in a baseunit 22, and is not in use. Telephone 10 also comprises another speaker18 and another microphone 20 in base unit 22, which are used in ahands-free, “speakerphone” mode. Telephone 10 also comprisesconventional alphanumeric keys 30 to enter a telephone number for acall, and conventional speakerphone mode button 31. If desired,telephone 10 can also include other conventional telephone features,unrelated to the present invention. Telephone 10 also includes a mutebutton 32 with internal mute status reminder function according to thepresent invention, as described below.

FIG. 2 illustrates some functional components/modules of the base unit22 of telephone 10. In the illustrated embodiment, microphone 20 in baseunit 22 is active regardless of whether the telephone 10 is operating inthe “speakerphone” mode and regardless of whether the mute button 32 isactive/set. Microphone 20 detects speech and other sounds that reach it.The other sounds can be background sounds such as a door opening orclosing, keys of a computer keyboard being pressed, a chair moving, airconditioning noise, etc. Microphone 20 converts the speech and othersounds it detects into corresponding, electrical analog signals, in aknown manner. If the mute button 32 is not active/not set, a knowncommunication module 39 processes these analog signals in a known mannerfor communication to other people, via a telephone line 35, connectedwith a telephone call. However, if the mute button 32 is active/set,then the communication module 39 will be disabled, and not process orcommunicate these analog signals to other people connected with thetelephone call. For those embodiments of the present inventioncomprising computer software, telephone 10 includes a CPU 36 and basicoperating system function 39 to execute the software, RAM 37 and ROM 38to store speech recognition software 45 prior to execution by CPU 36 viaRAM 37.

In accordance with the present invention, a threshold detection module40 compares, to a predetermined threshold, energy level or magnitude ofthe analog signals from the microphone 20. The threshold detectionmodule 40 may comprise an integrated circuit or other circuitry and/or acomputer program stored on ROM 38 for execution by processor 36 via RAM37. If the analog signal level is below the threshold, the source of thesounds is presumed to be background noise, and threshold detectionmodule 40 will deactivate an audio alarm 54. (In such a case in ahardware embodiment of the present invention, threshold detection module40 sends a “low” signal to AND gate 43, whose output is connected to an“Activate” input of audio alarm 54.) However, if the analog signal levelis above the threshold, then the threshold detection module will permitactivation of the audio alarm 54 (if other conditions, described below,are met). (In a hardware embodiment of the present invention, thresholddetection module 40 sends a “high” signal to AND gate 43 to permitactivation of audio alarm 54.) A speech recognition module 44, which issoftware executing on processor 36, an integrated circuit and/or othercircuitry, also analyzes the analog signal from the microphone 20. Inaccordance with one embodiment of the present invention, the speechrecognition module 44 attempts to recognize any words (in any humanvoice) in the analog signal, using known speech recognition algorithmsembodied in the software, integrated circuit and/or other circuitry. Byway of example, IBM ViaVoice speech recognition software containsalgorithms to perform speech recognition. Also, CMU Sphinx-III voicerecognition software and VoiceSignals voice recognition software containspeech recognition algorithms/modules based on hidden-markov model (HMM)representations of language. Such known speech recognition softwareprograms can be used in module 44 to attempt to recognize words and/orspeech patterns in the analog signals. If the speech recognition module44 does not identify any words in the analog signal, the speechrecognition module 44 presumes the analog signal to represent backgroundnoise and not an attempt by the user to communicate to the other personor people on the call. Consequently, the speech recognition module 44will deactivate the audio alarm 54. (In a hardware embodiment of thepresent invention, in such a case, speech recognition module 44 sends a“low” signal to AND gate 43.) However, if the speech recognition module44 identifies any words (in any human voice) from the analog signal,then the speech recognition module 44 will permit activation of theaudio alarm 54 to attempt to alert the user that the mute button isactive/set. (In a hardware embodiment of the present invention, in sucha case, speech recognition module 44 sends a “high” signal to AND gate43.) This signal will activate the audio alarm 54 if the thresholddetection module detected that the signal level exceeded the thresholdlevel and mute button 32 has been activated/set and has enabled audioalarm 44. The reason that speech recognition module 44 attempts toactivate the audio alarm (when it identifies one or more spoken words)is the presumption that the user of telephone 10 spoke the word(s) andintended to communicate the word(s) to the other person or people on thetelephone call. Upon hearing the alarm, the user will typicallydeactivate/reset the mute button and repeat the words that werepreviously muted. Because the audio alarm will sound near the beginningof the user's speech (as soon as the speech recognition module 44detects the first word or two), the user can deactivate/reset the mutebutton near the beginning of the user's speech, and may only have torepeat a few words. As noted above, if the mute button is active/set,but the speech recognition module 44 does not identify any words fromthe analog signal, then the speech recognition module 44 will notattempt to activate the audio alarm 54 and not alert the user that themute button is active/set. The reason that the module 44 will notattempt to activate the audio alarm 54 in this case is the presumptionthat the sounds were background noise, and not intended as acommunication from the user. If the mute button is not active/not set,the state of the mute button (switch) will disable the audio alarm 54,and will not permit the audio alarm to sound under any circumstances.This will avoid interfere with the user's attempts to communicate withthe other person or people on the call.

In accordance with another embodiment of the present invention, thespeech recognition module 44 not only recognizes words but also has beentrained to recognize the voice of the user (of telephone 10) anddistinguish words spoken by the user from the same words spoken by otherpeople. By way of example, a specific user can train a known ARMprocessor-based speech recognition program (such as IBM Via Voice speechrecognition software based on Hidden Markov Model) to recognize thespecific user's speech pattern, and differentiate it from otherbackground noise or other people's speech patterns. A “speech pattern”is the spectra of electrical signals generated by a microphone when aspecific person speaks words. More information on this speechrecognition program can be obtained from manufacturer's manuals such asthat from VoiceSignal company atwww.voicesignal.com/solutions/tech.php3#sda. This embodiment of thepresent invention operates the same as the foregoing embodimentdescribed above, except that the speech recognition module 44 onlyattempts to activate the audio alarm 54 if the speech recognition module44 detects, in the analog signal, a word or speech pattern spoken in thevoice of the user. This will avoid unnecessary audio alarms in caseswhere another person is speaking in the vicinity of the telephone. Forexample, there may be a secretary near the user or someone walking bythe user, and the secretary or other person is speaking loudly enough tobe detected by microphone 20 and exceed the threshold level of module40. This will not cause the speech recognition module 44 to attempt toactivate the audio alarm in this embodiment of the present invention.The audio alarm is not needed or desired in such cases because thesecretary or other person do not intend to communicate to the otherpeople on the telephone call, and therefore, there is no need to alertthe user of telephone 10 that the mute function is active/set.

FIG. 3 is a flow chart based on a combined hardware and softwareembodiment of threshold detection module 40 and speech recognitionmodule 44. Threshold detection module 40 comprises a threshold detector41 to determine whether the analog signal exceeds a threshold, and logic42 to process the output of the threshold detector 41. In thisembodiment, detector 42 is formed from circuitry, and logic 42 is formedfrom computer programming. Speech recognition module 44 comprises aspeech recognition function 45 to recognize spoken words represented bythe analog signal, and logic 46 to process the output of the speechrecognition function 45. In this embodiment, speech recognition function45 comprises circuitry and/or computer programming, and logic 46comprises computer programming. FIG. 3 is a flowchart of the programlogic 42 and program logic 46 in this embodiment of the presentinvention. Because threshold detector 41 and speech recognition function45 are well known, their mode of operation need not be repeated indetail herein. In step 100, logic 42 within the threshold detectionmodule 40 receives a signal from threshold detector 41. The signal fromthreshold detection function 41 indicates whether the power level,energy level or magnitude of the analog signal corresponding to thespeech or other sounds detected by the microphone 20 exceeds apredetermined threshold level. If not (decision 104, no branch), thenlogic 42 will not permit activation of the audio alarm 54 (step 106). Ifso (decision 104, yes branch), the first test for activating the audioalarm 54 is met, and the analysis of whether to activate the alarmproceeds to the next test. Accordingly, logic 46 within the speechrecognition module 44 has also received a signal from the speechrecognition function 45 indicating whether the speech recognitionfunction 45 has detected a real word in the analog signal (step 108). Ifnot (decision 110, no branch), then logic 46 will send a deactivationsignal to audio alarm 54 to prevent the audio alarm from sounding (step112). If so (decision 110, yes branch), then the second test foractivating the audio alarm is met, and the speech recognition logic 46sends an activation signal to the audio alarm 54 (step 118). If the mutebutton has been activated/set enabling the audio alarm 54, then theactivation signal from the logic 46 will cause the audio alarm 54 tosound its alarm. However, if the mute button has not been activated/set,then the audio alarm 54 will not be enabled and will not sound its alarmin response to the activation signal from the speech recognition logic46.

FIG. 4 is a flow chart based on a combined hardware and softwareembodiment of threshold detection module 40 and a speech recognitionmodule 144 (that substitutes for module 44 in FIGS. 1 and 2). Thresholddetection module 40 comprises threshold detector 41 to determine whetherthe analog signal exceeds a threshold, and logic 42 to process theoutput of the threshold detector 41. In this embodiment (as in theprevious embodiment), detector 41 is formed from circuitry, and logic 42is formed from computer programming. Speech recognition module 144comprises a speech recognition function 145 to recognize words spoken bya specific person, and logic 146 to process the output of the speechrecognition function 145. In this embodiment, speech recognitionfunction 145 comprises circuitry and/or computer programming, and logic146 comprises computer programming. FIG. 4 is a flowchart of the programlogic 42 and program logic 146 in this embodiment of the presentinvention. Because threshold detector 41 and speech recognition function145 are well known, their modes of operation need not be repeated indetail herein. In step 200, logic 42 within the threshold detectionmodule 40 receives a signal from threshold detector 41. The signal fromthreshold detection module 40 indicates whether the power level, energylevel or magnitude of the analog signal corresponding to the speech orother sounds detected by the microphone 20 exceeds a predeterminedthreshold level. If not (decision 204, no branch), then logic 42 willnot permit activation of the audio alarm 54 (step 206). If so (decision204, yes branch), the first test for activating the audio alarm 54 ismet, and the analysis of whether to activate the alarm proceeds to thenext test. Accordingly, logic 146 within the speech recognition module144 has also received a signal from the speech recognition function 145indicating whether the speech recognition function 145 has detected areal word in the analog signal from a specific person/recognized user(step 208). This is the person/user who has trained the speechrecognition function 145 to recognize this person's/user's voice anddistinguish this person's/user's voice from other people's voices.(Speech recognition function 145 will not send a signal to logic 146indicating that it has detected a real word in the specificperson's/user's voice when it detects a real word from another person orwhen it detects only background/nonword sounds.) If the speechrecognition function 145 has not detected a real word or speech patternin the analog signal from a specific person/recognized user (decision210, no branch), then logic 146 will deactivate audio alarm 54 so itcannot sound (step 212). However, if the speech recognition function 145has detected a real word or speech pattern in the analog signal from thespecific person/recognized user (decision 210, yes branch), then thesecond test for activating the audio alarm is met, and the speechrecognition logic 146 sends an activation signal to the audio alarm 54(step 218). If the mute button has been activated/set, then the audioalarm 54 is enabled and the activation signal from the speechrecognition logic 146 will cause the audio alarm 54 to sound. However,if the mute button has not been activated/set, then the audio alarm 54will not be enabled and will not sound the alarm in response to theactivation signal from the speech recognition logic 146.

Based on the foregoing, system, method and computer program forimplementing a mute function have been disclosed. However, numerousmodifications and substitutions can be made without deviating from thescope of the present invention. For example, the speech recognitionsoftware can be programmed to disable the mute function if the usercommands such disabling by spoken words. Therefore, the presentinvention has been disclosed by way of illustration and not limitation,and reference should be made to the following claims to determine thescope of the present invention.

What is claimed is:
 1. A method for controlling a mute function in atelephone device, the method comprising the steps of: while the mutefunction is active, voice recognition software in the telephone deviceprocessing sound detected by a microphone in the telephone device torecognize and identify one or more specific words as having been spokenby a specific person and not by another person, and in response, thetelephone device activating an alarm in the telephone device tocommunicate that the mute function is active, wherein the voicerecognition software was trained, prior to the sound having beendetected, to differentiate the one or more specific words spoken by thespecific person from the same one or more specific words spoken by otherpeople, wherein the method further comprises: while the mute function isactive, ascertaining that a magnitude of an analog signal representingthe detected sound exceeds a predetermined threshold, below which thedetected sound is identified as being noise, as part of the identifyingthat the specific word is spoken by the specific person, wherein theactivating the alarm is responsive to both the ascertaining and theidentification of the one or more specific words spoken by the specificperson.
 2. The method of claim 1, wherein the method further comprises:while the mute function is active, determining that a magnitude of ananalog signal representing another sound detected by the microphone doesnot exceed the predetermined threshold, and in response the telephonedevice deactivating the alarm.
 3. The method of claim 1, wherein thealarm is an audible sound.
 4. A computer program product for controllinga mute function in a telephone device, the computer program productcomprising a computer-readable storage device in the telephone deviceand program code stored on the storage device, wherein the program codecomprises: program instructions (i) to process, by voice recognitionsoftware while the mute function is active, sound detected by amicrophone in the telephone device and (ii) to recognize and identify,while the mute function is active, one or more specific words as havingbeen spoken by a specific person and not by another person, and inresponse, (iii) to activate, while the mute function is active, an alarmin the telephone device to communicate that the mute function is active,wherein the voice recognition software was trained, prior to the soundhaving been detected, to differentiate the one or more specific wordsspoken by the specific person from the same one or more specific wordsspoken by other people, wherein the program code further comprises:program instructions to ascertain while the mute function is active,that a magnitude of an analog signal representing the detected soundexceeds a which the detected sound is identified as being noise, as partof the identifying that the specific word is spoken by the specificperson, wherein the program instructions to activate the alarm isresponsive to both program instructions to ascertain and the programinstructions to identify the one or more specific word spoken by thespecific person.
 5. The computer program product of claim 4, wherein theprogram code further comprises: program instructions to determine, whilethe mute function is active, that a magnitude of an analog signalrepresenting another sound detected by the microphone does not exceedthe predetermined threshold, and in response to deactivate the alarm. 6.The computer program product of claim 4, wherein the alarm is an audiblesound.
 7. A telephone device, comprising: a mute function, a microphonefor sensing sound reaching the telephone device, a processor, a memory,a computer-readable storage device and program code stored on thestorage device for execution by the processor via the memory, whereinthe program code comprises: program instructions (i) to process, byvoice recognition software while the mute function is active, sounddetected by the microphone in the telephone device and (ii) to recognizeand identify, while the mute function is active, one or more specificwords as having been spoken by a specific person and not by anotherperson, and in response, (iii) to activate, while the mute function isactive, an alarm in the telephone device to communicate that the mutefunction is active, wherein the voice recognition software was trained,prior to the sound having been detected, to differentiate the one ormore specific words spoken by the specific person from the same one ormore specific words spoken by other people, wherein the program codefurther comprises: program instructions to ascertain, while the mutefunction is active, that a magnitude of an analog signal representingthe detected sound exceeds a predetermined threshold, below which thedetected sound is identified as being noise, as part of the identifyingthat the specific word is spoken by the specific person, wherein theprogram instructions to activate the alarm is responsive to both theprogram instructions to ascertain and the program instructions toidentify the one or more specific words spoken by the specific person.8. The telephone device of claim 7, wherein the program code furthercomprises: program instructions to determine, while the mute function isactive, that a magnitude of an analog signal representing another sounddetected by the microphone does not exceed the predetermined threshold,and in response to deactivate the alarm.
 9. The telephone device ofclaim 7, wherein the alarm is an audible sound.